[0001] The invention relates to color-forming carboxamidonaphthalene dye precursor compounds
and corresponding carboximide dyes that are useful in imaging materials, such as photographic
silver salt materials, and processes. The dye precursor compounds are 4-(4'-secondary
or tertiary-amino - anilino)-1-carboxamidonaphthalenes.
[0002] Photographic materials for producing silver images and dye images are known. The
dye image in such materials is produced by a coupling reaction in which a developing
agent is oxidized upon development of photosensitive silver halide in the material,
followed by reaction of the resulting oxidized form of the developing agent with a
coupling agent to produce a dye image.
[0003] A method of producing reversal color images, also known as positive dye images, which
involves developing a silver image in an imagewise exposed photographic material has
been suggested in, for example, U.S. Patent 4,035,184 and U.S. Patent 3,938,995. These
patents describe production of a dye image through oxidation, by oxidized developing
agent of the leuco form of an image dye. This leuco dye is the reaction product of
a color-forming coupler and a suitably substituted N,N-dialkyl-p-phenylenediamine
and is incorporated in the silver halide photographic material.
[0004] It has been desirable to provide alternative means for producing a dye image, especially
a dye image that enhances a silver image
[0005] The present invention provides a color-forming carboxamidonaphthalene dye precursor
compound comprising a benzene ring attached by an -NH- group to a naphthalene nucleus
wherein:
a) the benzene ring has a secondary or tertiary amino group in the para position relative
to the -NH- group;
(b) the naphthalene nucleus has a carboxamido group in the para position relative
to the -NH- group; and
(c) the benzene ring and the naphthalene nucleus are optionally further substituted;
the compound being capable, on oxidation, of forming a carboximide dye.
[0006] The dye precursor compounds of the invention provide a means for producing a dye
image, especially a dye image that enhances a silver image, without requiring a coupling
reaction. Further, the dye produced has good stability.
[0007] The dye produced from a dye precursor compound of the invention is a carboximide
dye comprising a benzene ring attached by an -N- group to a naphthalene nucleus in
quinone form wherein:
(a) the benzene ring has a secondary or tertiary amino group in the para position
relative to the -N- group;
(b) the naphthalene nucleus in quinone form has a carboximido group in the para position
relative to the -N- group; and,
(c) the benzene ring and the naphthalene nucleus in quinone form are optionally further
substituted.
[0008] The dye precursor compounds may be incorporated in photographic silver halide materials.
[0009] A stable dye image, especially a dye image that enhances a silver image, may be produced
in a photographic material comprising a support having thereon, preferably in a binder:
(a) photosensitive silver halide, and associated therewith (b) a color-forming dye
precursor of the invention by imagewise converting the precursor to a dye upon exposure
and processing of the photographic material. The dye may be formed by cross-oxidation,
preferably by means of a cross-oxidizing silver halide developing agent. A combination
of color-forming dye precursors may be used, if desired.
[0010] A positive dye image may be provided in a photographic material as just described
by a process comprising (a) developing a silver image in the exposed photographic
material using an alkaline photographic developer in the absence of a cross-oxidizing
silver halide developing agent; then, (b) fogging the residual silver halide, such
as by uniformly exposing the resulting material to a flash exposure of light or, alternatively,
a chemical fogging agent; followed by (c) producing a dye image by developing the
photographic material in an alkaline cross-oxidizing developer, such as a 3-pyrazolidone
cross-oxidizing developer; and, then (d) bleaching and fixing the photographic material
in a silver halide bleaching and fixing composition to produce the positive dye image.
After step (a) and before
step (b), optionally the photographic process for producing a positive dye image includes
a stop bath treatment. This permits a desirable lowering of the pH of the development
to a point at which development of a negative silver image stops quickly. This produces
an improved dye image upon processing.
[0011] A negative dye image and a negative silver image may be produced in an imagewise
exposed photographic material comprising, in association, (a) photosensitive silver
halide, and (b) a dye precursor of the invention by developing the photographic material
in an alkaline, cross-oxidizing, photographic silver halide developer composition,
preferably such a composition comprising a 3-pyrazolidone silver halide developing
agent. The negative dye image preferably enhances the negative silver image. This
enables a lower concentration of silver to be used in the photographic material before
exposure than otherwise might be necessary to form a similar developed image from
silver halide alone. When the negative, developed silver image is at least partially
removed from the photographic material, such as by means of a bleaching and fixing
composition, a negative dye image remains in the processed photographic material.
[0012] A positive dye image and a positive silver image may be produced in an imagewise
exposed photographic material comprising, in association, (a) direct-positive photographic
silver halide, and (b) a color-forming dye precursor of the invention by (A) developing
the photographic material using an alkaline, cross-oxidizing photographic silver halide
developing composition; then (B) fixing the resulting photographic material to produce
a positive dye image and a positive silver image.
[0013] In each of the photographic materials and processes described above, the resulting
naphthoquinoneimide dye in the image areas has good stability. The naphthoquinoneimide
dye exhibits an increase in stability compared to a corresponding benzoquinoneimide
dye. In the naphthoquinoneimide dyes, a ureido group provides increased stability
compared to corresponding dyes comprising other carboxamido groups than a ureido group.
[0014] In addition to the uses described above, the dye precursor compound of the invention
may be incorporated in a photographic silver halide processing composition for producing
a dye-enhanced silver image wherein the composition comprises a cross-oxidizing photographic
silver halide developing agent.
[0015] Preferred color-forming 4-(4'-secondary or tertiary-amino anilinop
i-carboxamidonaphthalene dye precursors of the invention are represented by the formula:

wherein,
R1 is alkyl, such as alkyl containing 1 to 25 carbon atoms, for example methyl, ethyl,
propyl, butyl, decyl and eicosyl; cycloalkyl containing 5 to 8 carbon atoms, for example
cyclohexyl and cyclopentyl; aryl, such as aryl containing 6 to 25 carbon atoms, for
example, phenyl, tolyl and xylyl; alkoxy, such as alkoxy containing 1 to 25 carbon
atoms, for example, methoxy, ethoxy, butoxy and decyloxy; aryloxy, such as aryloxy
containing 6 to 25 carbon atoms, for example, phenoxy, tertiary-butylphenoxy and di-tertiary-amylphenoxy;

or a 5 or 6 member heterocyclic group, for example a 5 or 6 member heterocyclic group
comprising atoms selected from nitrogen, oxygen, sulfur, carbon and hydrogen atoms,
for example, morpholino, pyrrolino, pyridino, pyrimidino, oxazolino, thiazolino, and
thiopheno;
R2, R3 , R4 , R5 , R6 andR7 are individually hydrogen; alkyl, such as alkyl containing 1 to 25 carbon atoms,
for example, methyl, ethyl, propyl, butyl, decyl and eicosyl; aryl, such as aryl containing
6 to 25 carbon atoms, for example, phenyl, tolyl and xylyl; alkoxy, such as alkoxy
containing 1 to 25 carbon atoms, for example, methoxy, ethoxy, butoxy and decyloxy;
arylsulfonyl (Ar-S02-), such as arylsulfonyl containing 6 to 25 carbon atoms, for example, phenylsulfonyl,
naphthylsulfonyl, xylylsulfonyl and tolylsulfonyl; chlorine; bromine; carbamoyl; sulfamoyl;
carboxy; sulfonamido; and carboxamido;
Re is hydrogen; alkyl, such as alkyl containing 1 to 25 carbon atoms, for example, methyl,
ethyl, propyl, butyl, decyl, eicosyl, hydroxyethyl, methylsulfonamidoethyl and tolylsulfonamidopropyl;
aryl, such as aryl containing 6 to 25 carbon atoms, for example phenyl, tolyl and
xylyl; acyl, such as acyl containing 2 to 25 carbon atoms, for example acetyl, ethanoyl,
heptanoyl, pivaloyl, undecanoyl, benzoyl and methylbenzoyl; carbamoyl, such as carbamoyl
containing 2 to 25 carbon atoms, for example methylcarbamoyl, ethylcarbamoyl, decylcarbamoyl,
and phenylcarbamoyl;
R9 is alkyl, such as alkyl containing 1 to 25 carbon atoms, for example methyl, ethyl,
propyl, butyl, decyl, eicosyl, hydroxyethyl, methylsulfonamidoethyl, tolylsulfonamidopropyl;
aryl, such as aryl containing 6 to 25 carbon atoms, for example phenyl, tolyl and
xylyl; acyl containing 2 to 25 carbon atoms, such as alkylcarbonyl containing 2 to
25 carbon atoms, for example acetyl, ethanoyl, heptanoyl, pivaloyl and undecanoyl,
or such as arylcarbonyl containing 7 to 25 carbon atoms, for example benzoyl and methylbenzoyl;
carbamoyl, such as carbamoyl containing 2 to 25 carbon atoms, for example methylcarbamoyl,
ethylcarbamoyl, decylcarbamoyl and phenylcarbamoyl;
R10 and R11 are individually hydrogen; alkyl, such as alkyl containing 1 to 25 carbon atoms,
for example, methyl, ethyl, propyl, butyl, decyl and eicosyl; aryl, such as aryl containing
6 to 25 carbon atoms, for example phenyl, tolyl and xylyl; an aliphatic carbocyclic
group, such as a 5 or 6 member carbocyclic group, for example, cyclohexyl, said carbocyclic
group optionally containing a total of 6 to 8 carbon atoms; or, taken together represent
the atoms, such as the oxygen, nitrogen, sulfur, carbon and hydrogen atoms, necessary
to complete a 5 or 6 member heterocyclic ring, such as pyrrolino, pyridino, pyrimidino,
thiazolino and oxazolino; and
R12, R13 , R14 and R15 are individually substituents that do not adversely affect desired photographic properties,
for instance, hydrogen; alkyl, such as alkyl containing 1 to 25 carbon atoms, for
example, methyl, ethyl, propyl, butyl, decyl and eicosyl; cyano (-CN); carboxamido;
sulfonamido; sulfamoyl; chlorine; bromine; and alkoxy, such as alkoxy containing 1
to 25 carbon atoms, for example, methoxy, ethoxy, propoxy and eicosyloxy; all alkyl
and aryl groups, when present as such or as part of another substituent, being optionally
substituted. by groups which do not adversely affect the dye precursors or the corresponding
dyes.
[0016] Examples of suitable substituted alkyl groups include alkyl containing a sulfonamido
group, such as CH
3SOzNH-, a carboxamido group, an alkoxy group, such as methoxy or ethoxy, hydroxy,
carboxyl (-COOH), an aryl group, alkylcarbonyl, such as methylcarbonyl and ethylcarbonyl,
arylcarbonyl, such as phenylcarbonyl, alkylamino, such as methylamino and ethylamino,
and arylamino, such as phenylamino. Another example of a substituted alkyl group is

[0017] An alkyl group containing an aryl substituent is also known as an aralkyl group e.g.
a benzyl group. Examples of suitable substituted aryl groups include phenyl containing
an alkoxy group, such as methoxy and ethoxy, carboxyl, alkyl such as methyl, ethyl,
propyl and butyl, and hydroxy. An especially useful substituted aryl group is an alkyl
substituted aryl group, such as tolyl, 2,4,6-triisopropylphenyl and t-butylphenyl.
An alkyl substituted aryl group is also known as an alkaryl group.
[0018] Particularly preferred dye precursors are those wherein R
1 is NH-R
10. A ureido group is provided on the naphthalene nucleus which enhances dye stability
and increases the ease of dye formation.
[0019] An example of a preferred class of color-forming compounds according to the invention
is represented by the formula:

wherein,
R16 is alkyl containing 1 to 25 carbon atoms, cycloalkyl containing 5 to 8 carbon atoms;
aryl containing 6 to 25 carbon atoms; alkoxy containing 1 to 25 carbon atoms; aryloxy
containing 6 to 25 carbon atoms; or

R17 is hydrogen, alkyl containing 1 to 25 carbon atoms or acyl containing 2 to 25 carbon
atoms;
R18 is alkyl containing 1 to 25 carbon atoms or acyl containing 2 to 25 carbon atoms;
R19 is hydrogen or alkyl containing 1 to 25 carbon atoms;
R20 is hydrogen, carboxamido or alkyl containing 1 to 25 carbon atoms; and,
R21 and R22 are individually hydrogen, alkyl containing 1 to 25 carbon atoms, aryl containing
6 to 25 carbon atoms or together are the atoms selected from carbon, hydrogen, nitrogen
and oxygen atoms necessary to complete a 5 or 6 member heterocyclic group, such as
morpholino, piperizino and pyrrolidino.
[0021] An especially preferred color-forming compound of this invention for use in a photographic
material comprising a support having thereon, in association, in a gelatino binder:
(a) photosensitive silver halide; and (b) a color-forming compound which is imagewise
converted upon exposure and processing of thematerial to a dye by cross-oxidation
by means of a cross-oxidizing developing agent, is represented by the formula:

[0022] As used herein, a carboxamido group means a group represented by the formula:

wherein R
23 is a substituent which does not adversely affect the color-forming dye precursor
or imide dye. R is, for example, alkyl containing 1 to 20 carbon atoms, such as methyl,
ethyl, propyl, butyl, decyl, and eicosyl, or aryl containing 6 to 20 carbon atoms,
such as phenyl and tolyl. Examples of such groups include phenylcarboxamido, methylcarboxamido
and tolylcarboxamido.
[0023] As used herein, a sulfonamido group means an unsubstituted sulfonamido group or a
sulfonamido group that is substituted by a group that does not adversely affect the
desired properties of the color-forming dye precursor. A sulfonamido group may be,
for example, a group represented by the structure:

wherein,
Z is a substituent, such as alkyl containing 1 to 25 carbon atoms, for example methyl,
ethyl, propyl, butyl, decyl and eicosyl, or aryl containing 6 to 25 carbon atoms,
such as phenyl, tolyl and naphthyl. Examples of sulfonamido groups include methylsulfonamido,
tolylsulfonamido, 2,4,6-triethylphenylsulfonamido, and 2,4,6-triisopropylsulfonamido.
[0024] As used herein, a carbamoyl group means an unsubstituted carbamoyl group or a carbamoyl
group that is substituted by a group that does not adversely affect the desired properties
of the color-forming dye precursor. A carbamoyl group herein means, for example, a
group represented by the structure:
wherein,

[0025] R
24 is a substituent, such as alkyl containing 1 to 25 carbon atoms, for example methyl,
ethyl, propyl, butyl, decyl and eicosyl, or aryl containing 6 to 25 carbon atoms,
such as phenyl, tolyl and naphthyl.
[0026] Examples of carbamoyl groups include methylcarbamoyl, ethylcarbamoyl, and phenylcarbamoyl.
[0027] As used herein, a sulfamoyl group means an unsubstituted sulfamoyl group or a sulfamoyl
group that is substituted by a group that does not adversely affect the desired properties
of the color-forming dye precursor. A sulfamoyl group herein means, for example, a
group represented by the structure:

wherein,
R28a and R24b are individually hydrogen or a substituent, such as alkyl containing 1 to 25 carbon
atoms, for example methyl, ethyl, propyl, butyl, decyl and eicosyl, or aryl containing
6 to 25 carbon atoms, such as phenyl, tolyl and xylyl.
[0028] Examples of sulfamoyl groups include: -SOzNH
2, -SOzNHCHs, -S0
2 NHCH
2 CH
3 ,

[0029] The color-forming dye precursors are prepared by condensation of a phenylenediamine
compound with a substituted halonitronaphthalene wherein the nitro group is in the
4 position with respect to a halogen atom on the naphthalene ring, followed by reduction
of the nitro group and subsequent formation of the amidonaphthalene from the intermediate
amine.
[0030] An illustrative method of preparation of a color-forming dye precursor according
to the invention is the preparation of 4 {-4-[N-(2-methylsulfonamidoethyl)ethylamino]-2-methylanilino]-1-(N'-octylureido)-naphthalene
as follows:
4-[N-(2-methylsulfonamidoethyl)ethylamino]-2-methylaniline (54.2 g, 0.2 mol) and 4-fluoro-l-nitronaphthalene
(32.2 g, 0.2 mol) were stirred at 85°C under nitrogen with pyridine (31.6 g, 0.4 mol)
in dimethylsulfoxide (500 ml) for 24 hours. The resulting mixture is then poured into
ice water and extracted with a suitable solvent, such as methylene chloride. The extract
is washed with water, dried and concentrated. The resulting intermediate product is
purified, such as by crystallization from ethanol to produce a purified intermediate
(m.p. 170-172°C). The resulting intermediate is reduced in dry tetrahydrofuran containing
a catalytic amount
of palladium on charcoal at 276 kPa (40 psi) hydrogen pressure in a Parr apparatus.
After removal of the catalyst, such as by filtration, octyl isocyanate is added to
the filtrate. The mixture is stirred for 16 hours, water (100 ml) is added and the
product is taken up in ether. The resulting solution is dried, filtered and concentrated.
The resulting product is purified, such as by recrystallization from methanol. The
purified compound has a melting point of 132-133°C.
[0031] Another example of a preparation according to the invention is the preparation of
4-(4'-N,N-diethylamino-2-methylanilino)-1-decanamidonaphthalene. This preparation
is as follows:
4-(4-N,N-diethylamino-2-methylanilino)-l-nitronaphthalene (12 g., 0.0034 mole) is
reduced in tetrahydrofuran (200 ml) on a Parr apparatus by means of a catalyst, such
as palladium on charcoal, at 276 kPa (40 pounds per square inch) hydrogen pressure.
The catalyst is then removed. Acid acceptor, such as triethylamine (11.2 ml, 0.08
mole) is added. Then decanoyl chloride (12.7 g., 0.0037 mole) in tetrahydrofuran (50
ml) is added drop-wise. The resulting mixture is stirred until reaction completion,
such as for about lb hours. Water is added and the product taken up with a solvent,
such as ether. Following drying and concentration of the solvent solution, the residue
is typically purified, such as by recrystallization from ethanol and then methanol,
to produce a white crystalline product having a melting point of 147 to 148°C.
[0032] The color-forming 4-(4'-secondary or tertiary-amino anilino)-l-carboxamidonaphthalene
dye precursors may be used in a photographic material and process in a range of concentrations.
Selection of an optimum concentration of the dye precursor or combination of such
dye precursors depends upon the desired image, the particular photographic material,
processing steps and conditions, other components in the photographic material, and
the particular dye precursor. A preferred concentration of dye precursor is within
the range of 0.1 to 0.6 mole of per mole of photosensitive silver halide in the photographic
material. An especially useful concentration of color-forming dye precursor is within
the range of 0.1 to 0.2 mole per mole of silver halide in the photographic material.
In a photographic material, a preferred concentration of color-forming dye precursor
is within the range of 0.5 to 22 mg per square decimeter of support, such as a concentration
within the range of 5 to 11 mg per square decimeter of support.
[0033] The hue of the dye produced from the color-forming dye precursor will vary, depending
upon such factors as the particular groups on the color-forming dye precursor, processing
conditions, other components in the photographic material such as dispersion solvents,
and whether a combination of dyes is present in the photographic material or not.
The color-forming dye precursor in the photographic material is preferably colorless
prior to exposure and processing. Some of the suitable color-forming dye precursors
have a slight color, such as a slight yellow color, in the photographic material.
This slight color is not considered unacceptable.
[0034] The color-forming dye precursor generally absorbs electromagnetic radiation outside
the visible region of the electromagnetic spectrum before imagewise exposure and processing
of the photographic material. The nature of the absorption and degree of absorption
of the color-forming dye precursor depends upon the nature, for the most part, of
the substituent groups on the color-forming dye precursor.
[0035] The photographic materials may comprise a photosensitive component which consists
essentially of photographic silver halide. Examples of useful photographic silver
halides are silver chloride, silver bromide, silver bromoiodide, silver chlorobromoiodide,
silver iodide and mixtures thereof. The silver halide may be present in the photographic
material in the form of an emulsion which is a dispersion of the photographic silver
halide in a suitable binder. The silver halide may be present in a range of grain
sizes from fine grain to coarse grain. Negative and direct positive silver halide
emulsions may be used. Such photographic emulsions are described in, for example,
Research Disclosure, December, 1978, Item No. 17643. A composition containing the
silver halide may be prepared by any of the well known procedures in the photographic
art, such as described in Research Disclosure, December 1978, Item No. 17643.
[0036] The photographic material may contain addenda commonly found to be useful in silver
halide photographic materials. These addenda include chemical sensitizers, brighteners,
antifoggants, emulsion stabilizers, light absorbing and scattering materials, hardeners,
coating aids, plasticizers, lubricants, antistatic materials, matting agents, and
development modifiers, as described in Research Disclosure, December 1978, Item No.
17643.
[0037] The photographic silver halide may be spectrally sensitized by means of spectral
sensitizing dyes, as described in, for example, Research Disclosure, December 1978,
Item No. 17643. Useful spectral sensitizing dyes include such dyes as polymethine
dyes which include the cyanines, merocyanines, complex cyanines and merocyanines (including
tri, tetra and polynuclear cyanines and merocyanines), as well as oxonols, hemioxonols,
styryls, merostyryls and streptocyanines. Combinations of spectral sensitizing dyes
may be used.
[0038] The photographic silver halide may be used in a range of concentrations in a photographic
material. An optimum concentration of photographic silver halide depends upon such
factors as the desired image, processing conditions, particular dye precursor, other
components of the photographic material and the particular photographic silver halide.
A preferred concentration of photographic silver halide is within the range of 2 to
7 moles of per mole of color-forming dye precursor in the photographic material. The
coverage of photographic silver halide is less than otherwise might be required, due
to the enhancing properties of the dye produced upon processing of the photographic
material.
[0039] The color-forming dye precursor may be in any location in a silver halide photographic
material which allows production of the desired dye upon processing. Thus, the color-forming
dye precursor may, if desired, be in a layer adjacent or contiguous to the layer comprising
the photosensitive silver halide.
[0040] The color-forming dye precursor is frequently Lmmobilized in an oil phase in the
photographic material. This enables the dye precursor to be dispersed satisfactorily.
Alternatively, the color-forming dye precursor is dispersed in a dispersion solvent
to produce a desired photographic material. Coupler solvents known in the photographic
art are useful for aiding dispersion of the color-forming dye precursor. Examples
of useful coupler solvents include N-n-butylacetanilide, diethyl lauramide, di-n-butyl
phthalate and 2,4-ditertiaryamylphenol. The color-forming dye precursor may also be
loaded into a latex or a nonsolvent dispersion may be prepared, if desired.
[0041] Many developing agents are useful for developing an image in the photographic material.
Any silver halide developing agent is may be used, provided it comprises a cross-oxidizing
developing agent which will cross-oxidize with the color-forming dye precursor. Such
a silver halide developer, called herein a cross-oxidizing developing agent, becomes
oxidized during development by reducing exposed silver halide to silver metal. The
oxidized developer then cross-oxidizes the color-forming dye precursor to form the
desired dye.
[0042] A cross-oxidizing developing agent (COD) enables the color-forming dye precursor
to become oxidized without the color-forming dye precursor itself developing silver.
The cross-oxidizing developing agent is viewed alternatively as an electron transfer
agent which shuttles electrons between the developing silver halide and the color-forming
dye precursor.
[0043] The requirements for a cross-oxidizing developing agent are: (a) the developing agent
must have sufficient, electrochemical potential under the conditions of use to develop
exposed silver halide, (b) in its oxidized form, the developing agent must be of such
electrochemical potential as to oxidize the color-forming dye precursor, and (c) in
its oxidized form, the developing agent must be stable to decomposition by other chemical
reactions for a sufficient period to undergo the redox reaction with the color-forming
dye precursor. Whether a developing agent is a cross-oxidizing developing agent or
not depends upon whether the oxidized form is sufficiently stable and the oxidizing
potential is such that an effective transferral of electrons occurs through whatever
phase barriers exist during cross-oxidizing development. Whether a particular developing
agent meets these requirements depends upon the conditions under which development
occurs. Other factors influence whether a particular developing agent is a cross-oxidizing
developer, including the pH of the developing composition, the temperature of the
development process and the length of development time. Examples of developing agents
which are useful as cross-oxidizing developing agents include 3-pyrazolidone developers,
such as l-phenyl-3-pyrazolidone, l-phenyl-4,4-dimethyl-3-pyrazolidone and 4-hydroxymethyl-4-methyl-l-phenyl-3-pyrazolidone.
Such cross-oxidizing developing agents are described in, for example, U.S. Patent
3,938,995. Combinations of non-cross-oxidizing developing agents and cross-oxidizing
developing agents are useful, provided a minor proportion of the non-cross-oxidizing
developing agent is present, such as less than about 10 percent of the total combination
is non-cross-oxidizing developing agent. Examples of combinations of a non-cross-oxidizing
developing agent and a cross-oxidizing developing agent include 4-hydroxymethyl-4-methyl-l-phenyl-3-pyrazolidone
with a minor proportion of at least one of the following non-cross-oxidizing developing
agents:ascorbic acid, hydroquinone and pyrimidine. Selection of an optimum cross-oxidizing
silver halide developing agent or developing agent combination will depend upon such
factors as the desired image, the particular photosensitive silver halide, processing
conditions, and the particular color-forming dye precursor.
[0044] A silver halide developing agent or silver halide developing agent combination may
be incorporated in the photographic material. Generally, the silver halide developing
agent is most useful in a processing solution in which the photographic material is
processed after exposure.
[0045] The developing agent may be used in a range of concentration in the photographic
material or in a processing composition in which the photographic material is processed.
A preferred concentration of developing agent in the photographic material is within
the range of 0.01 to 1.0 mole of developing agent per mole of color-forming dye precursor
in the photographic material. A preferred concentration of developing agent in a processing
solution for processing a photographic material containing a color-forming dye precursor
is within the range of 0.5 to 2 grams of developing agent per liter of processing
solution.
[0046] The term "developing agent" herein includes compounds which are developing agents
or developing agent precursors. That is, those compounds are included which are not
developing agents in the photographic material until a condition occurs, such as contact
with a suitable activator for the photographic material.
[0047] The tone of the silver image and dye image produced in the photographic material
will vary, depending upon such factors as the silver morphology of the developed silver
image, the covering power of the silver materials, the particular dye formed, the
particular developing agent, processing conditions, and other components in the photographic
material. In photographic materials that provide a brown silver image, a dye produced
is preferably complementary in hue to the silver image. A combination of dyes and
a silver image that produce a neutral-appearing image are preferred.
[0048] The photographic materials may comprise a variety of binders alone or in combination.
The binders include both naturally occurring substances, such as proteins, for example,
gelatin, gelatin derivatives, cellulose derivatives, polysaccharides, such as dextran,
and gum arabic; but also include synthetic polymeric materials, such as water-soluble
polyvinyl compounds, e.g. poly(vinylpyrrolidone) and acrylamide polymers. Examples
of useful binders include those described in, for instance, Research Disclosure, December
1978, Item No. 17643.
[0049] The photographic materials may contain an overcoat layer, and/or interlayer, and/or
subbing layer to provide desired properties. The overcoat layer, for example, increases
resistance to abrasion and other markings on the material. The overcoat layer, interlayer
or subbing layer contain, alone or in combination, the described binders.
[0050] A photographic material may comprise a variety of supports. Useful supports include
those that are resistant to adverse changes in structure due to processing conditions
and which do not adversely affect the desired sensitometric properties of the photographic
materials. Examples of useful supports include cellulose ester, poly(vinylacetal),
poly(ethylene terephthalate) and polycarbonate films, as well as related films and
resinous materials. Glass, paper and metal supports are also useful. A flexible support
is preferred.
[0051] The photographic coating compositions may be coated on a support by procedures known
in the photographic art. Such procedures include, for example, immersion or dip coating,
roller coating, reversal roll coating, airknife coating, doctor blade coating, spray
coating, extrusion coating, bead coating, stretch flow coating and curtain coating.
[0052] The photographic materialsmay be imagewise exposed by means of various forms of energy
to produce a developable image. Such forms of energy include those to which the photosensitive
silver halide is sensitive, and encompass ultraviolet, visible and infrared regione
of the electromagnetic spectrum, as well as electron beam and beta radiation, gamma
ray, X-ray, alpha particle, neutron radiation and other forms of corpuscular wave-like
radiant energy in either coherent or non-coherent forms. Lasers may used, for example.
Exposures are monochromatic orthochromatic or panchromatic depending on the spectral
sensitization of the photosensitive silver halide. Imagewise exposure is generally
for a sufficient time and intensity to produce a developah latent image in the photographic
material.
[0053] A photographic material containing a dye precursor according to the invention may
be processe in (a) a process which produces a positive dye image (b) a process which
produces a negative dye image an negative silver image, (c) a process which produces
negative


material is processed following exposure to form a visible image. This is done, for
example, by associating the silver halide at one stage of the process with an aqueous
alkaline medium in the presence of a cross-oxidizing developing agent contained in
the medium and/or in the photographic material.
[0054] To produce a positive dye image, also known as a reversal dye image, it is desirable
to process the exposed photographic material by means of a non-cross-oxidizing developing
composition as a first development step. During this step, the exposed silver halide
is reduced to elemental silver by the non-cross-oxidizing developing composition.
The non-cross-oxidizing developing composition does not, when oxidized, oxidize the
color-forming dye precursor according to the invention to its corresponding dye.
[0055] The non-cross-oxidizing developer composition useful in this step may be an alkaline
solution, preferably an aqueous solution comprising a non-cross-oxidizing developing
agent. Non-cross-oxidizing developing agents are known in the photographic art and
include many silver halide developing agents which will reduce exposed photosensitive
silver halide to silver, but will not oxidize the color-forming dye precursor to a
corresponding dye. Examples of useful non-cross-oxidizing developing agents are described
in, for example, Research Disclosure, December 1978, Item No. 17643. Useful non-cross-oxidizing
developers include developer compositions comprising ascorbic acid, hydroquinone,
pyrimidine developing agents and a combination of hydroquinone and N-methyl-p-aminophenol.
[0056] In a second step of the process for forming a positive dye image, fogging of the
photographic material is accomplished by exposing the photographic material to light
or by chewical fogging by means of chemical fogging agents known in the photographic
art.
[0057] Following the described fogging step, a second silver halide developing step is carried
out. This is carried out by means of a cross-oxidizing developing composition. It
is in this step that the color-forming dye precursor is converted to a dye in the
image areas. Any silver halide developing composition is useful in this step, provided
that it cross-oxidizes the color-forming dye precursor to a desired dye. Such silver
halide developing compositions include alkaline solutions comprising a cross-oxidizing
silver halide developing agent, preferably a 3-pyrazolidone cross-oxidizing silver
halide developing agent. This cross-oxidizing developing agent becomes oxidized during
development by reducing exposed or fogged silver halide to silver metal. The oxidized
developing agent then cross-oxidizes the color-forming dye precursor to a desired
dye. The photographic material, upon processing, contains a concentration of dye in
inverse proportion to the amount of exposure of the photographic material. That is,
a positive dye image, also described herein as a reversal dye image, is formed.
[0058] An especially useful process for producing a positive dye image in an imagewise exposed
photographic material containing a dye precursor of the invention comprises: (a) developing
the exposed photographic material in an alkaline photographic developer in the absence
of a cross-oxidizing silver halide developing agent, and then (b) uniformly exposing
the material to a flash exposure of light, followed by (c) developing the photographic
material in an alkaline, cross-oxidizing developer, comprising an aqueous, alkaline
solution of 4-methyl-4-hydroxymethyl-l-phenyl-3-pyrazolidone, and (d) bleaching and
fixing the photographic material in a silver halide bleaching and fixing solution
to produce a positive dye image. It may be preferred to treat the photographic material
by means of a development stop bath after step (a) and before step (b).
[0059] Photographic materials containing a dye precursor according to the invention are
also useful for producing negative dye images. Such negative dye images may be produced
in an exposed photographic element comprising a support having thereon, in reactive
association, in a binder, (a) photosensitive silver halide, and (b) a color-forming
4-(4'-secondary or tertiary-aminoanilino)-1-carboxamidonaphthalene dye precursor by
(A) developing the photographic element in an alkaline, cross-oxidizing photographic
silver halide developer composition to produce a negative dye image and silver image;
then (B) removing at least part of the silver image from the photographic material,
such as by bleaching and fixing the silver from the material. Removal of the silver
is accomplished by means of bleaching and fixing compositions known in the photographic
art. The optimum bleaching and fixing compositions are selected to provide the desired
dye image. Suitable bleaching and fixing compositions are described in Grant Haist.
Modern Photographic Processing, Vol. 2, Chapter 10 (1979). The bleaching agent employed
should be of such strength that it does not oxidize the color-forming dye precursor
and thereby lead to uniform dye density in the material.
[0060] Photographic materials containing a dye precursor according to the invention comprising

images. A process of producing a positive dye image and a positive silver image in
an imagewise exposed- photographic material comprising a support having thereon, in
reactive association, in a binder, (a) direct-positive photographic silver halide,
and (b) a color-forming 4-(4'-secondary or tertiary-amino anilino)-l-carboxamidonaphthalene
dye precursor, comprises (A) developing the photographic element in an alkaline, cross-oxidizing
photographic silver halide developing composition; then (B) fixing the resulting photographic
material to produce a positive dye image and a positive silver image. Useful direct-positive
silver halide is described in, for example, Research Disclosure, December 1978, Item
No. 17643, pages 22 through 31. Fixing the photographic material is accomplished by
means of fixing compositions known in the photographic art, such as a sodium thiosulfate
fixing composition.
[0061] An advantage of the photographic material and process is that the dye images produced
upon processing possess desired stability to post-processing conditions and visible
light exposure. A simple test is useful for establishing the degree of stability which
is desired for a dye image produced from a color-forming dye precursor according to
the invention. One such test is a test well known in the photographic art in which
a processed photographic material is exposed to a Simulated Average North American
Skylight (SANS) with continuous 5400 LUX of exposure at an average temperature of
21°C at 45 percent relative humidity. A comparison of the stability of the tested
dye is then observed.
[0062] When a cross-oxidizing silver halide developing agent is present in the photographic
material, a developed image is produced after imagewise exposure of the photographic
material by contacting the material with an alkaline activator solution which enables
development of the exposed silver halide, as well as production of the desired dye.
Many alkaline activators are useful for developing an image in a photographic material
comprising an incorporated cross-oxidizing silver halide developing agent. Alkaline
activators which are known to be useful in the photographic art, such as in stabilization
processing, are useful for developing an image in the described photographic material.
Examples of useful alkaline activators include sodium hydroxide, potassium hydroxide,
trisodium phosphate . 12H20 (pH 12), sodium metaborate (pH 12), disodium phosphate
and monosodium phosphate. An optimum alkaline activator will depend upon such factors
as the desired image, the particular cross-oxidizing developing agent, processing
conditions and the particular color-forming dye precursor. An especially useful alkaline
activator comprises trisodium phosphate (pH 12).
[0063] The alkaline activator may be used in a range of concentrations. A preferred concentration
of alkaline activator is within the range of 10 to 50 grams per liter of activator
solution which produces a pH within the range of 11 to 12. An optimum concentration
of alkaline activator will depend upon such factors as the desired image, the particular
activator, processing conditions, particular cross-oxidizing developing agent, particular
photosensitive silver halide and particular color-forming dye precursor.
[0064] After exposure and processing, the photographic material comprises a dye image or,
alternatively, a dye image and a silver image. Preferred dyes are represented by the
formula:

wherein, R
1 , R
2 , R
3 , R
4 , R
5 , R
6 , R , R
8 , R
9, R
10 , R
11, R
12,R
13,R
14 and R
15 are as defined.
[0066] The naphthoquinoneimide dyes have increased stability to hydrolysis compared to corresponding
benzoquinoneimide dyes. This is believed to be due at least in part to the resistance
which naphthoquinoneimide dyes exhibit to formation of a resonance structure that
favors formation of an indoaniline dye.
[0067] The following examples are included for a further understanding of the invention.
Example 1 Preparation of 4-{4'-(N-(2-methylsulfonamidoethyl)etaylamino]-2-methyl-
anilino}-1-(N'-octylureido)-naphthalene:
[0068]

[0069] A solution of 4-[N-(2-methylsulfonamidoethyl)ethylamino]-2-methylaniline (54.2 g,
0.2 mol) and 4-fluoro-l-nitronaphthalene (32.2 g, 0.2 mol) with pyridine (31.6 g,
0.4 mol) in dimethylsulfoxide (500 ml) was stirred and heated under a nitrogen atmosphere
at 85°C for 24 hours. The reaction mixture was then poured into ice water and extracted
with methylene chloride. The extract was washed three times with water, dried, and
concentrated. After crystallization from ethanol, an intermediate product (30.4 g,
34% yield, m.p. 171-173°C) was characterized by nuclear magnetic resonance, mass spectral
and elemental analysis.
[0070] A sample of the resulting intermediate (6.0 g, 0.014 mol) was reduced in dry tetrahydrofuran
(150 ml) containing a catalytic amount of palladium on charcoal at 276 kPa (40 psi)
hydrogen pressure in a Parr Apparatus. After removal of the catalyst by filtration,
octyl isocyanate (2.1 g, 0.014 mol) was added to the filtrate. The mixture was stirred
for 16 hours, then water (100 ml) was added and the product was taken up in ether.
The ethereal solution was dried, filtered and concentrated. The residue was recrystallized
twice from methanol. The crystalline product (4.7 g, 59% yield, m.p. 132-133°C) was
characterized by nuclear magnetic resonance and elemental analysis.
Example 2 Preparation of 4-(4'-N,N-diethyl- amino-2-methylanilino)-I-de- canamidonaphthalene:
[0071]

4-(4-N,N-diethylamino-2-methylphenyl-amino)-1-nitronaphthalene (5.0 g, 0.014 mol)
was reduced in tetrahydrofuran (200 ml) in a Parr Apparatus using palladium on charcoal
catalyst at 276 kPa (40 psi) hydrogen pressure. After removal of the catalyst by filtration,
first triethylamine (3 g, 0.03 mol) was added and then decanoyl chloride (3.0 g, 0.016
mol) in tetrahydrofuran (50 ml) was added drop-wise. The mixture was stirred for 16
hours. Then water (150 ml) was added and the product taken up with ether. Following
drying (by means of Na
2SO
4), filtration and concentration of the ether solution, the residue was recrystallized
from ethanol and then methanol. The resulting white crystalline product (2.4 g, 36%
yield, m.p. 147-148°C) was characterized by nuclear magnetic resonance, mass spectral
and elemental analysis.
Examples 3-7 Use in Photographic Material
[0072] In each of the following examples a photographic material was prepared by coating
the following photographic composition on a subbed poly(ethyleneterephthalate) film
support:
1) silver bromoiodide (0.8 micron grain, sulfur and gold chemically sensitized) (9.7
mg/dm2)
2) color-forming dye precursor as coupler solvent dispersion (1:1 to 1:2 parts by
volume) (3.0 to 16.2 mg/dm2) (coverage of dispersion was adjusted to give an approximate silver plus dye density
of 2.0)
3) photographic gelatin (binder) (43.2 mg/dm2), hardened by bis(vinylsulfonylmethyl)ether ((CH2=CHSU2CH2)2O) (2.0 parts by weight in 200 parts water, 0.43 mg/dm2).
[0073] Each photographic material was chemically oxidized at 22°C in the following processing
sequence:
1) 30 second fix in the following fixing composition:

2) 60 second water wash
3) 30 second oxidizing treatment in the following oxidizing composition:

4) 5 minute water wash
5) 10 second water wash (in Kodak Photo-Flo Solution, which is a trademark of and
available from Eastman Kodak Company, U.S.A.)
6) dry in air at room temperature (about 21°C). The resulting dried photographic materials
were then exposed (emulsion side to the light) tc 5400 LUX irradiation (Simulated
Average North American Skylight irradiation) for 1, 3 and 7 days. Density was measured
at the maximum absorption wavelength for each dye. The percentage of dye fade was
calculated based on the following formula:

wherein D equals density. Results of these examples are summarized in following Table
I:


Examples 8-10
[0074] The dyes listed in following Table II were prepared by procedures similar to those
described:

Examples 11 - 16
[0075] In each of the following Examples a photographic material was prepared as described
in Examples 3-7. The photographic material in each case was imagewise exposed to light
to produce a developable latent image in the photographic material. The exposed material
was then processed at 22°C in the following processing sequence:
1) 30-second development by immersion in the following composition:

2) 2-minute water wash
3) 30-second fix in the fixing composition described in step 1 of Example 3
4) 2-minute water wash
5) dry in air at room temperature (about 21°C). The resulting dried photographic materials
were then exposed (emulsion side to the light) to 5400 LUX irradiation (Simulated
Average North American Skylight irradiation) for 1, 3 and 7 days. Density was measured
at the maximum absorption wavelength for each dye. The percentage of dye fade was
calculated as described in Example 3. A dye image and silver image was produced in
each example. Results of the percentage of dye fade are summarized in following Table
III:

[0076] The following compounds were prepared by procedures similar to those described in
Examples 1 and 2:
